Toxic antifouling material



GE 29341913G UNITED STATES PATENT OFFICE TOXIC AN TIFOULING MATERIAL Loren C. Hurd, Madison, Wis., assignor to Wisconsin Alumni Research Foundation No Drawing. Application January 8, 1931, Serial No. 507,439

1 Claim.

My invention relates to a toxic composition which is especially adaptable as an anti-fouling material for preventing the infestation with barnacles or growth of marine organisms on ships bottoms and other objects the surfaces of which .N are exposed to fouling from such causes.

The prevention or elimination of fouling infestation of ships bottoms due to these causes has presented a problem of great economic importance. Tremendous increase in fuel expense and delays in sailings and other conditions are the direct result of the fouling of ships bottoms.

I have discovered and established by experiment the fact that the toxic characteristics of tellurium, either in its elemental form or in the form of organic or inorganic compounds thereof, are practically completely effective when present on exposed surfaces, in preventing infestation by barnacles or other marine growths. The presence of the toxic characteristics of tellurium actually renders the exposed surfaces practically immune to any tendency of barnacles to attach themselves to the surfaces and to prevent the growth of marine organisms, and particularly animal organisms, in such manner that they are rendered ineffective as fouling agencies. The only practical commercial method of treating the surfaces is by the application of the material in the form of paint or coating material, although it is also practicable to impregnate the object with the material. Where iron or steel surfaces are to be treated, however, it is preferable to apply the composition as a coating so that it can include materials which will serve as a protection against corrosion.

In accordance with my invention, I incorporate tellurium in a suitable form in a vehicle which can be applied by any of the usual methods, such as brushing, spraying or impregnation. While tellurium in its elemental form can be treated in a manner which will enable it to be incorporated in a suitable paint vehicle, it is much more practicable and inexpensive from a commercial standpoint to prepare a product composed of a tellurium compound, either organic or inorganic,

and introduce this product into a suitable vehicle which will render the composition capable of application by the desired method. Various compounds of tellurium, either organic or inorganic, are efiective as a toxic base for anti-fouling paints, but I have found in my experiments and 1 tests that zinc tellurite is especially effective for the purpose, and as an instance of a suitable compositon I give below a formula for a paint ve- The above formula involves an inorganic compound of tellurium, but it will be understood that organic compounds of tellurium, such, for instance, as ethyl telluride (C2H5)zTe, may be utilized .as a toxic base for the composition.

It is understood that my invention contemplates tellurium as a toxic base for any composition for the treatment of s firfades against fouling by barnacles or marine growths, and that any of the compounds, either organic or inorganic, of tellurium, for this purpose, are contemplated as being within the scope and spirit of my invention. The manner or method in which these compounds are prepared and the character of vehicle or the method of associating the compounds with the vehicle may be accomplished as desired by those skilled in the art, but it will be understood that my invention involves a product in which tellurium in any form is utilized as a toxic ingredient in anti-fouling compositions, whether the composition is to be applied as a paint or coating material or as an impregnating material.

I claim:

An anti-fouling marine paint toxic to marine animal organisms comprising a suitable vehicle having incorporated therein zinc tellurite.

LOREN C. HURD. 

